2019 Assessment of the Arrowtooth Flounder Stock in the Gulf of Alaska

Arrowtooth Flounder (ATF) was considered the most abundant groundfish species in the Gulf of Alaska during the first decade of this century, but its biomass shifted to less than that of Pacific Ocean Perch, based on the 2017 Gulf of Alaska groundfish survey. Projections for 2016 from the 2015 GOA assessments estimated Pacific Ocean Perch at 457,768 t and ATF at 2,103,860 t. However, survey biomass estimates of Pacific Ocean Perch in the 2017 survey were higher than arrowtooth (over 1.5 million t vs. 1,053,695 t).

Arrowtooth Flounder biomass estimates in the current model have changed relative to previous assessments. The model projection of spawning biomass for 2020, assuming fishing mortality equal to the recent 5-year average, was 756,100 t, 93 percent of the projected 2020 spawning biomass from the 2018 assessment of 810,158 t. The 2020 and 2021 ABCs using F_ABC=0.193 from this assessment model were lower than the 2018 ABC of 145,841 t; 128,060 t and 124,357 t. The 2020 and 2021 OFLs estimated in this assessment were 153,017 t and 148,597 t. The projected estimate of total biomass for 2020 was down by 3 percent from the 2018 assessment of 1,367,620 t, to 1,325,867 t. Despite the declines, the Arrowtooth Flounder stock in the Gulf of Alaska is not being subjected to overfishing and is not approaching a condition of being overfished.